1. Field of the Invention
The present invention relates to a mobile terminal, a contents delivery system, and a contents reproduction program which allow the mobile terminal to receive contents in good condition in the case where the communication quality is deteriorated during the contents delivery service using the terminal, for example, a portable phone, a PHS (Personal Handyphone System), a PDA (Personal Digital Assistant) unit equipped with a radio communication function, and a notebook PC.
2. Related Art
The contents delivery service provided through the mobile phone for distributing such contents as movie and music has been well known. Today, in order to cope with the demand for the delivery of the contents data with higher quality, the size of the contents data to be delivered has been increased.
When the user of the mobile phone moves to a place where the communication environment is not well-organized, the communication quality of the mobile phone is likely to be deteriorated. In the case where the access from a large number of users concentrates on a single radio base station, the communication band allocated for each user is reduced, thus degrading the communication quality. Despite the improved quality of the contents data to be delivered, the user has difficulty in receiving stable delivery of high quality contents data.
Patent Application Publication No. 2005-20312 (Patent Document 1) discloses the contents delivery system that delivers the contents, including voice and image data, without interruption of the voice communication.
In the aforementioned contents delivery system, upon reception of the contents delivery request from the mobile unit, the contents server transmits the image data to the mobile unit via the mobile packet communication network. Upon reception of the image data transmitted from the contents server, the mobile unit starts storing the image data, and sends the command for transmitting the voice data to the contents server. In response to the voice data transmission request, the contents server transmits the voice data to the mobile unit via the line switching network.
The contents server is structured to transmit the image data and the voice data via different networks. The communication quality of the line switching network for transmitting the voice data may be maintained stable even if the communication quality is degraded in the mobile packet communication network for transmitting the image data. This allows the mobile unit to receive at least the voice data with good communication quality.    [Patent Document 1] Patent Application Publication No. 2005-20312 (page 5, FIGS. 1 and 4)